1. Field of the Invention
The invention relates is directed to a device for coupling the coolant duct of a rotating part.
2. Description of the Prior Art
Reference DE-PS 42 07 042 discloses a generic device for coupling the coolant duct of a back-up and transporting roll. This device is supported by pins in bearing blocks or pillow blocks by roller bearings, and coolant flows through the device along an axial bore hole that is guided through the pins. Every bearing block is closed by a cover. The cover has a cooling duct which is connected at one end to a coolant inlet and coolant outlet, respectively. The other end opens into the region of the pin bore hole. A compensator is arranged between the duct opening of the cover and the bore hole of the roll and cooperates with a seal which coaxially contacts a sealing face arranged relative to the roll shaft. The seal is preferably constructed as a lip seal.
It is disadvantageous in this construction that the sealing lip of the sealing ring is subject to wear because of the movement occurring on it and therefore has a limited life. Further, the attainable temperature range is limited because lip sealing rings are usually made from elastomers. Moreover, the compensator cannot be pretensioned in a deliberate manner, so that it is not possible to adapt to different internal pressures of the coolant.